A comparison of Book II, chapters xxii and xxiii of Procopius' History of the Wars with Book II, chapter v of Thucydides' Peloponnesian War demonstrates the influence the classical historian had on the Byzantine writer. The episodes of plague that attacked Athens and Byzantium are constructed in nearly identical fashion. Both provide extensive descriptions of the course of the disease: its geographic origins, symptoms, variations, and effects. Both establish themselves as eyewitnesses to most of the things they report. And both writers reflect on topics such as the futile efforts of the physicians and the effect of the plague on general morality, but leave it to others to explain the reasons why the terrible disease arose in the first place. Thucydides' account clearly provided a model for Procopius. But the resemblance between the two historians is not just superficial and the method of reporting the story of the plague also reflects their specific approach to history. Both historians, even though they found themselves in the midst of all the horrifying sights and suffering they describe, suppress the personal in their accounts and attain an almost clinical tone. The objectivity of their reports is a rhetorical strategy meant to establish the truthfulness and reliability of their accounts. Thus Procopius adopted not just Thucydides' style but his conception of history-writing as well.
The similarities between the two historians is not limited to their chapters on the plague. Similarities appear from the beginning of the two books in opening sections in which the two state their reasons for writing and establish the grounds of their reliability. At the same time, of course, they ascribe high import to the events about which they write and, by extension, to the political entities and leading figures involved in these events. Thucydides announced that he had decided to write about the war from its very beginning because,...